[v9] fix: forward StrictMode

[CodyJasonBennett]

Respects React.StrictMode from parent renderers in R3F's Canvas. Targeting v9 since this highlights a lot of bugs in surrounding libraries that we'll want to take care of. This should probably be implemented downstream in a major.

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[krispya]

How do you feel about merging this? Seems like a good feature for us.

[CodyJasonBennett]

We have to add this for sure, but wondering whether we should let people opt in/out between v8 and v9.

[krispya]

As in a prop on Canvas? I would expect opting out means removing React.StrictMode.

[CodyJasonBennett]

Fair enough. I was moreso concerned about whether to backport as an opt-in flag to v8, but I'll leave it be since we'd just remove it in v9.

[krispya]

Yeah and I think very few people would actually opt-in. It's one of those changes that is technically correct but certainly going to introduce users insulated from React's disruptive change a year later.